A combined Johnson-Cook and Zerilli-Armstrong model for hot compressed typical high-strength alloy steel

The effects of strain rate and forming temperature on the deformation behaviors of typical high-strength alloy steel were investigated by uniaxial hot compression tests with the temperature range of 850-1150 °C and strain rates of 1-50 s−1. Based on the experimental results, the Johnson-Cook and Zerilli-Armstrong models were established for the studied alloy steel. However, the comparisons between the measured and predicted flow stress by Johnson-Cook and Zerilli-Armstrong models indicate some significant deviations in most loading conditions. This is because these two models overlook the coupled effects of strain rate-temperature-strain. Therefore, a combined Johnson-Cook and Zerilli-Armstrong (JC-ZA) model was developed to describe the relationship of the flow stress, strain rate and forming temperature. Results show that the stress-strain values predicted by the proposed model well agree with experimental ones, which confirmed that the combined JC-ZA model gives an accurate and precise estimate of the flow stress for the studied typical high-strength alloy steel.